A paddy field water level monitoring device and a monitoring method

Abstract

The application discloses a kind of paddy field water level monitoring device and monitoring method, the monitoring device disclosed in the application is measured by polar plate voltage, accurately measure water level height, additionally set conductivity meter or micro polar plate carries out conductivity detection, completes conductivity correction, and set water temperature meter carries out water temperature detection, completes water temperature correction, so that monitoring data is more accurate, single-chip microcomputer can complete the entry, transmission and display of the data required in detection process by man-machine interface or input-output interface, the monitoring method disclosed in the application can establish the relationship curve of accurate water level and measured voltage, voltage-conductivity standard relationship curve and voltage-(water level, conductivity) calibration surface under the same conductivity and different water temperature, the water level of rice field is realized accurate measurement by the relationship curve of water level and measured voltage, conductivity and water temperature correction are completed by voltage-conductivity standard relationship curve and voltage-water temperature calibration curve under different water temperature, and multi-dimension ensures measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of water level monitoring, and in particular to a paddy field water level monitoring device and monitoring method. Background Technology

[0002] Currently, the sensing technologies in the field of water level measurement are mainly divided into pressure-based, acoustic-optical, and image recognition methods. Pressure sensors measure water levels by utilizing the characteristic that the pressure exerted on a diaphragm in water changes with the water level. Their accuracy is generally around 3mm, and their range is typically over 1m. As a contact sensor, they offer good measurement accuracy and are suitable for many water level monitoring scenarios. Acousto-optic sensors calculate the distance between the sound source and the water surface by utilizing the time or phase change of sound or light waves after reflection from the water surface, thus converting it into a water level value. Their measurement accuracy can reach several millimeters, and their range is generally several meters or even tens of meters. As a non-contact sensor, they are suitable for measuring the water level of liquids with radioactivity, corrosiveness, or non-conductivity. Image recognition methods use image processing technology to identify water levels, also a non-contact water level measurement technique. Their accuracy depends on the measurement range, image resolution, and the reliability of the image processing algorithm. Generally, the larger the measurement range of the captured water level image and the wider the shooting angle, the lower the spatial resolution of the image for a given camera pixel count, resulting in lower water level measurement resolution. Conversely, a smaller measurement range can improve the measurement resolution, achieving higher accuracy. However, this technology relies heavily on camera pixels and algorithm reliability, making it more expensive.

[0003] In the field of paddy field water level monitoring, pressure sensors and acoustic-optical sensors are currently widely used. When pressure sensors are placed in paddy fields for a long time, sediments such as mud and sand in the paddy fields can easily clog the pressure diaphragm, resulting in inaccurate measurements. Acoustic-optical sensors require stable fixed poles to be erected in the field, which is costly. In addition, they also affect field machinery operations, so they are not suitable for widespread use.

[0004] With the increasing prominence of the aging population in my country's agricultural sector and the advancement of large-scale and intensive agricultural production models, the need for precise control of field irrigation and drainage is becoming increasingly urgent. Water level monitoring is a crucial basis for achieving precise irrigation and drainage in farmland. Currently, the main water level sensors on the market cannot meet the requirements of low cost, low power consumption, high reliability, and high accuracy for paddy field water level monitoring. There is an urgent need for a new type of monitoring device to meet the demand for small-range, high-precision water level measurement in the complex environment of paddy fields. Summary of the Invention

[0005] Purpose of the invention: The first purpose of this invention is to provide a low-power, low-cost, precise monitoring device for paddy field water levels. The second purpose of this invention is to provide a precise monitoring method for paddy field water levels, so as to solve the above-mentioned technical problems.

[0006] Technical Solution: The present invention provides a paddy field water level monitoring device, comprising a pair of relatively fixed electrode plates, a DC regulated power supply, a first relay, a first sampling resistor, and a microcontroller. The electrode plates include a first electrode plate and a second electrode plate. One end of the first electrode plate is electrically connected to the positive terminal of the DC regulated power supply. One end of the second electrode plate is electrically connected to one end of the first sampling resistor and to the microcontroller. The other end of the first sampling resistor is electrically connected to one end of the first relay switch. The other end of the first relay switch is electrically connected to the negative terminal of the DC regulated power supply. The first relay is electrically connected to the microcontroller. The electrode plates are conductive.

[0007] Furthermore, the microcontroller is equipped with a timer module.

[0008] Furthermore, the bottoms of the first and second electrode plates are flush.

[0009] Furthermore, it also includes a conductivity meter, which is electrically connected to the microcontroller.

[0010] Furthermore, it also includes a pair of microplates fixed in relative positions. The microplates include a first microplate and a second microplate. One end of the first microplate is electrically connected to the positive terminal of the DC regulated power supply. One end of the second microplate is electrically connected to one end of the second sampling resistor and is electrically connected to the microcontroller. The other end of the second sampling resistor is electrically connected to one end of the second relay switch. The other end of the second relay switch is electrically connected to the negative terminal of the DC regulated power supply. The second relay is electrically connected to the microcontroller. The microplates are conductive.

[0011] Furthermore, the second relay can be combined with the first relay and use the same relay.

[0012] Furthermore, the size of the microplate is no greater than 5×5mm, and the distance between the first microplate and the second microplate is no greater than 20mm.

[0013] Furthermore, it also includes a water thermometer, which is electrically connected to a microcontroller.

[0014] Furthermore, the surface of the electrode plate is made of a material or coating with good conductivity and strong stability, such as graphite or metal.

[0015] Furthermore, the surface of the microplate is made of a material or coating with good conductivity and strong stability, such as graphite or metal.

[0016] The present invention provides a method for monitoring water levels in paddy fields, comprising the following steps:

[0017] S1: Place the electrode plate on the surface of the paddy field to be tested, with the length direction of the electrode plate perpendicular to the surface of the paddy field. When the water level in the paddy field changes, the area of ​​the electrode plate submerged in the water changes accordingly.

[0018] S2: Set the calibration process in the controller of the microcontroller, collect the voltage across the first sampling resistor (4) at a finite number of determined water levels, and obtain the relationship curve between the water level and the measured voltage through overall or piecewise mathematical fitting. The calibration process does not need to be performed before each measurement. It can be embedded in the microcontroller program at the beginning, or it can be measured once when needed.

[0019] S3: During sampling, the microcontroller controls the first relay to close and then starts the timer. After a fixed delay, the voltage across the first sampling resistor is collected, and the length of the plate submerged in the paddy field water layer is calculated, which is the water level depth of the paddy field.

[0020] S4: Perform the next sampling after a fixed delay.

[0021] Furthermore, the S2 calibration process also includes measuring the conductivity of the water body to be tested, and obtaining voltage-water level calibration curves under different conductivity levels through overall or piecewise mathematical fitting; S3 also includes conductivity correction, using the conductivity measurement value and the voltage-water level calibration curves under different conductivity levels preset in the microcontroller controller, and using an interpolation algorithm to calculate the measured water level value.

[0022] Furthermore, the S2 calibration process also includes measuring the conductivity and temperature of the water body to be tested, and establishing a multiple regression or artificial intelligence model between the water temperature, conductivity, sampling resistor voltage in the electrode pair circuit and the actual water level, which is embedded in the microcontroller. S3 also includes conductivity and temperature correction. Based on the measured voltage, conductivity and water temperature, the established multiple regression or artificial intelligence model is used to invert the paddy field water level to achieve accurate measurement.

[0023] Furthermore, the conductivity correction step is as follows: the conductivity meter is placed in water at a position close to the electrode plate, and the measured water level value is calculated by using interpolation algorithm, multiple regression or artificial intelligence model based on the water layer conductivity measured by the conductivity meter and the voltage-water level calibration curves under different conductivity values ​​preset in the microcontroller controller.

[0024] Furthermore, the conductivity correction step is as follows: placing the microplate at the bottom of the electrode plate; measuring the conductivity of the water body using a standard conductivity meter and simultaneously recording the voltage of the second sampling resistor in the microplate circuit, establishing a voltage-conductivity standard relationship curve for the microplate; during the water level measurement process using the electrode plate, firstly calculating the conductivity of the water body to be measured by inverting the measured value of the microplate; using this conductivity value and the voltage-water level calibration curves preset in the microcontroller controller for different conductivity levels, calculating the measured water level value using interpolation algorithms, multiple regression, or artificial intelligence models.

[0025] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0026] (1) By measuring voltage to invert paddy field water level, accurate measurement of paddy field water level was achieved;

[0027] (2) Conductivity correction is performed by setting up a conductivity meter and / or microplates to further improve measurement accuracy;

[0028] (3) By setting the water thermometer, water layer temperature correction is performed to further improve measurement accuracy;

[0029] (4) The measuring range of the device provided by the present invention can reach 120% of the vertical height of the electrode plate above the water surface;

[0030] (5) The device provided by the present invention also has the advantages of low cost, low power consumption and small size;

[0031] (6) The method provided by this invention can establish a precise relationship curve between water level and measurement voltage, a standard relationship curve between voltage and conductivity, and a voltage-(conductivity, water level) calibration curve at different water temperatures. The water level in paddy fields can be accurately measured by inverting the relationship curve between water level and measurement voltage. Conductivity and water temperature correction can be completed by using the standard relationship curve between voltage and conductivity and the voltage-(conductivity, water level) calibration curve at different water temperatures. The measurement accuracy is ensured in multiple dimensions. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the first embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the structure of the second embodiment of the present invention;

[0034] Figure 3 The water level-voltage calibration curves (below 20cm water level) were obtained under different conductivity values ​​when using a 20cm long electrode plate.

[0035] Figure 4 The water level-voltage calibration curves (above 20cm water level) were obtained under different conductivity values ​​when using a 20cm long electrode plate. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1

[0038] The present invention provides a paddy field water level monitoring device, such as... Figure 1As shown, the device includes a pair of relatively fixed, flush-bottomed, and conductive electrode plates 1, a DC regulated power supply 2, a first relay 3, a first sampling resistor 4, a microcontroller 5, a conductivity meter 6, and a water thermometer 10. The electrode plates 1 are rectangular, with a length of 20cm and a width of 2cm. The electrode plates 1 include a first electrode plate 101 and a second electrode plate 102. One end of the first electrode plate 101 is electrically connected to the positive terminal of the DC regulated power supply 2. One end of the second electrode plate 102 is electrically connected to one end of the first sampling resistor 4 and is also electrically connected to the microcontroller 5. The other end of the first sampling resistor 4 is electrically connected to one end of the first relay 3 switch. The other end of the first relay 3 switch is electrically connected to the negative terminal of the DC regulated power supply. The first relay 3 is electrically connected to the microcontroller 5. The microcontroller 5 is equipped with a timer module. The conductivity meter 6 is electrically connected to the microcontroller 5, and the water thermometer 10 is electrically connected to the microcontroller 5.

[0039] Before measurement, electrode 1 is placed on the surface of the paddy field to be measured, with its length perpendicular to the paddy field surface. Based on the electrode length of 20cm, the water level measurement range of this device is 0-24cm. The bottom is aligned with the measurement starting point. When the water layer in the paddy field changes, the areas of the first electrode 101 and the second electrode 102 submerged in the water change accordingly. During sampling, the microcontroller 5 controls the first relay 3 to close and starts the timer. After a fixed delay, the voltage across the first sampling resistor 4 is collected, and the length of the electrode submerged in the paddy field water layer is calculated, which is the water level depth. The conductivity value is measured by the conductivity meter 6 and transmitted to the microcontroller 5. The voltage-water level calibration curves under different conductivity values ​​obtained from multiple experiments are used, and the measured water level value is calculated using an interpolation algorithm for conductivity correction. A water thermometer 10 is placed in the water near the electrode plate 1. The water temperature value is measured by the water thermometer 10 and transmitted to the microcontroller 5. The voltage-(conductivity, water level) calibration surface at different water temperatures obtained from multiple experiments is used, and an interpolation algorithm is employed to calculate the measured water level value for water temperature correction. In this embodiment, the water level is measured through the design of the electrode plate 1 and the first sampling resistor 4. In addition, a conductivity meter 6 and a water thermometer 10 are set up to detect conductivity and water temperature respectively, thereby completing the correction of conductivity and water temperature, making the monitoring data more accurate. At the same time, a microcontroller 5 is set up, which can complete the input, transmission and display of the data required during the detection process through a human-machine interface or an input-output interface.

[0040] The measurement method specifically includes the following steps:

[0041] S1: Place the electrode plate 1 on the surface of the paddy field to be tested. The length direction of the electrode plate 1 is perpendicular to the surface of the paddy field. When the water layer in the paddy field changes, the area of ​​the electrode plate 1 submerged in the water changes accordingly.

[0042] S2: The calibration process is set in the controller of the single-chip microcomputer 5. The voltage across the first sampling resistor 4 is collected at a finite number of determined water levels. The relationship curve between the water level and the measured voltage is obtained through overall or piecewise mathematical fitting.

[0043] S3: During sampling, the microcontroller 5 controls the relay 3 to close and then starts the timer. After a fixed delay, the voltage across the first sampling resistor 4 is collected, and the length of the plate 1 submerged in the paddy field water layer is calculated, which is the water level depth of the paddy field.

[0044] S4: Perform conductivity correction. Place the conductivity meter in water at a position close to the electrode plate. Based on the water layer conductivity measured by the conductivity meter and the voltage-water level calibration curves for different conductivity levels preset in the microcontroller, use an interpolation algorithm to calculate the measured water level value.

[0045] S5: Perform temperature correction. Based on the water layer temperature measured by the water thermometer 10 and the voltage-(conductivity, water level) calibration surface preset in the single-chip microcomputer 5 controller at different water temperatures, use the interpolation algorithm to calculate the measured water level value.

[0046] S6: Perform the next measurement after a fixed time interval.

[0047] Example 2

[0048] The present invention provides a paddy field water level monitoring device, such as... Figure 2 As shown, the device includes a pair of relatively fixed, flush-bottomed, and conductive electrode plates 1, a DC regulated power supply 2, a first relay 3, a first sampling resistor 4, a microcontroller 5, a microplate 7, a second sampling resistor 8, a second relay 9, and a water thermometer 10. The electrode plates 1 include a first electrode plate 101 and a second electrode plate 102. One end of the first electrode plate 101 is electrically connected to the positive terminal of the DC regulated power supply 2. One end of the second electrode plate 102 is electrically connected to one end of the first sampling resistor 4 and also electrically connected to the microcontroller 5. The other end of the first sampling resistor 4 is electrically connected to one end of the first relay 3 switch, and the other end of the first relay 3 switch is electrically connected to the DC regulated power supply 2. The negative terminal of the DC regulated power supply is electrically connected. The first relay 3 is electrically connected to the microcontroller 5. The microcontroller 5 is equipped with a timer module. The water thermometer 10 is electrically connected to the microcontroller 5. The microplate 7 includes a first microplate 701 and a second microplate 702. One end of the first microplate 701 is electrically connected to the positive terminal of the DC regulated power supply 2. One end of the second microplate 702 is electrically connected to one end of the second sampling resistor 8 and is electrically connected to the microcontroller 5. The other end of the second sampling resistor 8 is electrically connected to one end of the second relay 9 switch. The other end of the second relay 9 switch is electrically connected to the negative terminal of the DC regulated power supply. The second relay 9 is electrically connected to the microcontroller 5.

[0049] Before measurement, electrode 1 is placed on the surface of the paddy field to be measured, with its length perpendicular to the surface and its bottom aligned with the measurement starting point. As the water level in the paddy field changes, the submerged areas of the first electrode 101 and the second electrode 102 change accordingly. Simultaneously, micro-electrode 7 is placed in water at a similar location. The size of micro-electrode 7 is no larger than 5×5mm, and the distance between the two electrodes is no greater than 20mm. During measurement, micro-electrode 7 is completely submerged in the water body to be measured, with a depth from the water surface greater than three times the vertical height of the electrode. A standard conductivity meter is used to measure the conductivity of the water body, and the voltage of the second sampling resistor 8 in the circuit of micro-electrode 7 is simultaneously recorded to establish a voltage-conductivity standard relationship curve. In actual measurement, the conductivity value measured by the micro-electrode is replaced by the conductivity meter and transmitted to the microcontroller 5. The voltage-water level calibration curves obtained from multiple experiments under different conductivity levels are input, and an interpolation algorithm is used to calculate the measured water level value for conductivity correction. A water thermometer 10 is placed in the water near the electrode plate 1. The water temperature value is measured by the water thermometer 10 and transmitted to the microcontroller 5. The voltage-water temperature calibration curves obtained from multiple experiments at different water temperatures are used, and an interpolation algorithm is employed to calculate the measured water level value for water temperature correction. In this embodiment, the water level is measured through the design of the electrode plate 1 and the first sampling resistor 4. Additionally, a micro-electrode 7 and the water thermometer 10 are used to detect conductivity and water temperature respectively, thereby completing the conductivity and water temperature correction and making the monitoring data more accurate. Simultaneously, the microcontroller 5 is included, which can complete the input, transmission, and display of data required during the detection process through a human-machine interface or input / output interface.

[0050] The measurement method specifically includes the following steps:

[0051] S1: Place the electrode plate 1 on the surface of the paddy field to be tested. The length direction of the electrode plate 1 is perpendicular to the surface of the paddy field. When the water layer in the paddy field changes, the area of ​​the electrode plate 1 submerged in the water changes accordingly.

[0052] S2: The calibration process is set in the controller of the microcontroller 5. The voltage across the first sampling resistor 4 is collected at a finite number of determined water levels. The relationship curve between the water level and the measured voltage is obtained through overall or piecewise mathematical fitting. The conductivity and temperature of the water body to be measured are measured. A multivariate regression or artificial intelligence model between the water temperature, conductivity, plate-to-plate voltage of the sampling resistor in the circuit and the real water level is established and embedded in the microcontroller controller.

[0053] S3: Place the microplate at the bottom of the electrode plate; use a standard conductivity meter to measure the conductivity of the water body and simultaneously record the voltage of the second sampling resistor in the microplate circuit to establish a standard voltage-conductivity relationship curve of the microplate. When using the electrode plate to measure the water level, first calculate the conductivity of the water body to be measured by inverting the measured value of the microplate. At the same time, place the water thermometer 10 in the water near the electrode plate 1. Based on the measured voltage, conductivity and water temperature, use the established multiple regression or artificial intelligence model to invert the paddy field water level to achieve accurate measurement.

[0054] S4: Perform the next measurement after a fixed time interval.

Claims

1. A rice field water level monitoring device characterized by, The application relates to a water level measuring device for rice field, which comprises a pair of fixed-position polar plates (1), a direct-current stabilized power supply (2), a first relay (3), a first sampling resistor (4), a single-chip microcomputer (5), a pair of fixed-position micro polar plates (7), wherein the micro polar plates (7) comprise a first micro polar plate (701) and a second micro polar plate (702), one end of the first micro polar plate (701) is electrically connected with the positive terminal of the direct-current stabilized power supply (2), one end of the second micro polar plate (702) is electrically connected with one end of a second sampling resistor (8) and the single-chip microcomputer (5), the other end of the second sampling resistor (8) is electrically connected with one end of a second relay (9), the other end of the second relay (9) is electrically connected with the negative terminal of the direct-current stabilized power supply (2), the second relay (9) is electrically connected with the single-chip microcomputer (5), and the micro polar plates (7) have conductivity; the polar plates (1) comprise a first polar plate (101) and a second polar plate (102), one end of the first polar plate (101) is electrically connected with the positive terminal of the direct-current stabilized power supply (2), one end of the second polar plate (102) is electrically connected with one end of the first sampling resistor (4) and the single-chip microcomputer (5), the other end of the first sampling resistor (4) is electrically connected with one end of the first relay (3), the other end of the first relay (3) is electrically connected with the negative terminal of the direct-current stabilized power supply, the first relay (3) is electrically connected with the single-chip microcomputer (5), the polar plates (1) have conductivity, and the water level measuring device further comprises a water temperature meter (10) which is electrically connected with the single-chip microcomputer (5); the single-chip microcomputer (5) is provided with a timer module.

2. The water level monitoring device for rice field according to claim 1, wherein The first polar plate (101) and the second polar plate (102) are flush at the bottom.

3. The water level monitoring device for rice field according to claim 1, wherein The micro polar plates (7) are replaced by conductivity meters (6), and the conductivity meters (6) are electrically connected with the single-chip microcomputer (5).

4. The water level monitoring device for rice field according to claim 3, wherein The size of the micro polar plates (7) is not greater than 5*5 mm, and the distance between the first micro polar plate (701) and the second micro polar plate (702) is not greater than 20 mm.

5. A method of monitoring water level in a rice field, characterized by, The application further discloses a water level measuring method for rice field, which comprises the following steps: S1: placing the polar plates (1) on the surface of a rice field to be measured, with the length direction of the polar plates (1) being perpendicular to the surface of the rice field, and the area of the polar plates (1) being immersed in water changing with the water layer of the rice field; S2: setting a calibration process in the controller of the single-chip microcomputer (5), collecting the voltage between the two ends of the first sampling resistor (4) at a limited number of determined water levels, and obtaining the relationship curve between the water level and the measured voltage through overall or segmented mathematical fitting, the calibration process further comprising measuring the conductivity and temperature of the water body to be measured, adopting a multiple regression or artificial intelligence model established among the water temperature, the conductivity, the polar plate and the sampling resistor voltage, and embedding the model in the single-chip microcomputer controller; S3: when sampling, the single-chip microcomputer (5) controller controls the first relay (3) to be closed and then starts the timer, collects the voltage between the two ends of the first sampling resistor (4) after a fixed time delay, calculates the length of the polar plates (1) immersed in the water layer of the rice field, that is, the water level depth of the surface of the rice field, and carries out conductivity and temperature correction, inverses the water level of the rice field according to the measured voltage, the conductivity and the water temperature, and realizes accurate measurement by using the established multiple regression or artificial intelligence model. S4: After a fixed time delay, the next sampling is performed.

6. The water level monitoring method for rice field according to claim 5, wherein, The calibration process of step S2 further comprises measuring the conductivity of the water body to be measured, and obtaining the voltage-water level calibration curve at different conductivities by overall or segmented mathematical fitting; step S3 further comprises performing conductivity correction, and using the conductivity measurement value and the voltage-water level calibration curve at different conductivities preset in the single-chip microcomputer controller to calculate the measured water level value by using an interpolation algorithm.

7. The water level monitoring method for rice field according to claim 5 or 6, characterized in that, The conductivity correction step is: placing the conductivity meter in the water near the electrode plate (1), and calculating the measured water level value by using an interpolation algorithm, multiple regression or an artificial intelligence model according to the water layer conductivity measured by the conductivity meter (6) and the voltage-water level calibration curve at different conductivities preset in the single-chip microcomputer controller.

8. The water level monitoring method for rice field according to claim 5 or 6, characterized in that, The conductivity correction step is: placing the micro electrode plate (7) at the bottom of the electrode plate (1); using a standard conductivity meter to measure the water conductivity and record the voltage of the second sampling resistor (8) in the micro electrode plate circuit at the same time, establishing the voltage-conductivity standard relationship curve of the micro electrode plate, and in the process of water level measurement using the electrode plate (1), first calculating the conductivity of the water body to be measured by inversion of the measurement value of the micro electrode plate, and using the conductivity value and the voltage-water level calibration curve at different conductivities preset in the single-chip microcomputer controller to calculate the measured water level value by using an interpolation algorithm, multiple regression or an artificial intelligence model.

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